Underwater Robots to Repair Coral Reefs

Researchers at Heriot-Watt University in Scotland are developing underwater microrobots that could be sent in swarms to save coral reefs. The so-called coralbots would be programmed to piece together coral that have been damaged by bottom-trawling fishing or hurricanes, allowing them to regrow.

The university says, "The deep waters west of Scotland are characterized by the occurrence of large reef-forming corals similar to those in the tropics. Scottish reefs provide homes to thousands of other animals including fish and sharks, and are crucial to supplying coral propagules all the way to the Arctic. But Scottish corals are threatened by adverse impacts of bottom fishing that damages and kills large areas of reef. Luckily, this species can sometimes survive this damage and re-grow, but this can take many decades to centuries."

Before this project, scuba divers would take on the task of visiting areas of damaged coral and re-cementing broken fragments back to the reef, but that type of work takes time and scuba divers can only stay underwater for so long. Robots on the other hand have no limit to the time they can be underwater and they can also reach greater depths where some types of coral grow.

The robots will be programmed to follow a simple sets of rules where they collect coral fragments and then re-cement them to the reef. They'll be a driven by a computer trained to recognize coral fragments compared to rocks, sponges or other sea creatures.

To more efficiently rescue the coral, the small robots will work in swarms -- each programmed with a very simple task, but as a group they'll tackle a more complex operation. This not only makes the work faster, but it also eliminates the need to develop a more robust large robot to complete the job, which is time and cost efficient on the engineering side.

Dr. Lea-Anne Henry, from the School of Life Sciences, who is leading the project, said, “Swarms of robots could be instantaneously deployed after a hurricane or in a deep area known to be impacted by trawling, and rebuild the reef in days to weeks, instead of years to centuries."